platform/x86: thinkpad_acpi: Add support for X1 Yoga (2016) Tablet Mode

For whatever reason, the X1 Yoga doesn't support the normal method of
querying for tablet mode. Instead of providing the MHKG method under the
hotkey handle, we're instead given the CMMD method under the EC handle.
Values on this handle are either 0x1, laptop mode, or 0x6, tablet mode.

Tested-by: Daniel Martin <consume.noise@gmail.com>
Signed-off-by: Lyude <lyude@redhat.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>

diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt
index 72a150d8f3dfa58975a7ed05d0371e475e059e5b..ba2e7d2548429a249a2462cf58a24938245ee047 100644 (file)
--- a/Documentation/laptops/thinkpad-acpi.txt
+++ b/Documentation/laptops/thinkpad-acpi.txt
@@ -540,6 +540,7 @@ Events that are propagated by the driver to userspace:
 0x6022         ALARM: a sensor is extremely hot
 0x6030         System thermal table changed
 0x6040         Nvidia Optimus/AC adapter related (TO BE VERIFIED)
+0x60C0         X1 Yoga 2016, Tablet mode status changed
 
 Battery nearly empty alarms are a last resort attempt to get the
 operating system to hibernate or shutdown cleanly (0x2313), or shutdown

diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index f3053de25cc52c3fe90a8b5ddedc4d0d9022a7b8..cd956de7c1b2348bb5aa013b122532b448369392 100644 (file)
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -190,6 +190,9 @@ enum tpacpi_hkey_event_t {
        TP_HKEY_EV_LID_OPEN             = 0x5002, /* laptop lid opened */
        TP_HKEY_EV_TABLET_TABLET        = 0x5009, /* tablet swivel up */
        TP_HKEY_EV_TABLET_NOTEBOOK      = 0x500a, /* tablet swivel down */
+       TP_HKEY_EV_TABLET_CHANGED       = 0x60c0, /* X1 Yoga (2016):
+                                                  * enter/leave tablet mode
+                                                  */
        TP_HKEY_EV_PEN_INSERTED         = 0x500b, /* tablet pen inserted */
        TP_HKEY_EV_PEN_REMOVED          = 0x500c, /* tablet pen removed */
        TP_HKEY_EV_BRGHT_CHANGED        = 0x5010, /* backlight control event */
@@ -305,6 +308,8 @@ static struct {
        enum {
                TP_HOTKEY_TABLET_NONE = 0,
                TP_HOTKEY_TABLET_USES_MHKG,
+               /* X1 Yoga 2016, seen on BIOS N1FET44W */
+               TP_HOTKEY_TABLET_USES_CMMD,
        } hotkey_tablet;
        u32 kbdlight:1;
        u32 light:1;
@@ -2062,6 +2067,8 @@ static void hotkey_poll_setup(const bool may_warn);
 
 /* HKEY.MHKG() return bits */
 #define TP_HOTKEY_TABLET_MASK (1 << 3)
+/* ThinkPad X1 Yoga (2016) */
+#define TP_EC_CMMD_TABLET_MODE 0x6
 
 static int hotkey_get_wlsw(void)
 {
@@ -2086,10 +2093,23 @@ static int hotkey_get_tablet_mode(int *status)
 {
        int s;
 
-       if (!acpi_evalf(hkey_handle, &s, "MHKG", "d"))
-               return -EIO;
+       switch (tp_features.hotkey_tablet) {
+       case TP_HOTKEY_TABLET_USES_MHKG:
+               if (!acpi_evalf(hkey_handle, &s, "MHKG", "d"))
+                       return -EIO;
+
+               *status = ((s & TP_HOTKEY_TABLET_MASK) != 0);
+               break;
+       case TP_HOTKEY_TABLET_USES_CMMD:
+               if (!acpi_evalf(ec_handle, &s, "CMMD", "d"))
+                       return -EIO;
+
+               *status = (s == TP_EC_CMMD_TABLET_MODE);
+               break;
+       default:
+               break;
+       }
 
-       *status = ((s & TP_HOTKEY_TABLET_MASK) != 0);
        return 0;
 }
 
@@ -3125,11 +3145,16 @@ static int hotkey_init_tablet_mode(void)
        int in_tablet_mode, res;
        char *type;
 
-       /* For X41t, X60t, X61t Tablets... */
        if (acpi_evalf(hkey_handle, &res, "MHKG", "qd")) {
+               /* For X41t, X60t, X61t Tablets... */
                tp_features.hotkey_tablet = TP_HOTKEY_TABLET_USES_MHKG;
                in_tablet_mode = !!(res & TP_HOTKEY_TABLET_MASK);
                type = "MHKG";
+       } else if (acpi_evalf(ec_handle, &res, "CMMD", "qd")) {
+               /* For X1 Yoga (2016) */
+               tp_features.hotkey_tablet = TP_HOTKEY_TABLET_USES_CMMD;
+               in_tablet_mode = res == TP_EC_CMMD_TABLET_MODE;
+               type = "CMMD";
        }
 
        if (!tp_features.hotkey_tablet)
@@ -3921,6 +3946,12 @@ static bool hotkey_notify_6xxx(const u32 hkey,
                *ignore_acpi_ev = true;
                return true;
 
+       case TP_HKEY_EV_TABLET_CHANGED:
+               tpacpi_input_send_tabletsw();
+               hotkey_tablet_mode_notify_change();
+               *send_acpi_ev = false;
+               break;
+
        default:
                pr_warn("unknown possible thermal alarm or keyboard event received\n");
                known = false;